My aim will be to improve our understanding of sensory information processing systems in the retina. I will examine the role of a class of cells in the mouse retina, the F-miniON retinal ganglion cells (RGCs), in encoding information about the visual world. Retinal ganglion cells form the output of the retina, and their axons comprise the optic nerve. To stimulate and observe these neurons, I will use light pattern stimuli projected onto an ex vivo mouse retina with electrophysiological recordings and computational modeling analysis. To advance my analysis of population coding, I will implement multi-neuron recording via calcium imaging. My project consists of three specific aims. The first aim is to investigate the previously-reported direction selectivity of these RGCs, in comparison to other well-studied forms of direction selectivity in the visual system. I hypothesize that an offset of input excitatory and inhibitory receptive fields underlies this mechanism. The second aim is to investigate a role for these RGCs in the detection of visual contours. I hypothesize that contour detection first takes place in the retina, and will compare the mechanisms to those identified in visual cortex, the canonical site of contour and object detection. The third aim is to expand my study of these RGCs by incorporating multiple neuron recording. I will use dual cell electrophysiology and calcium activity imaging to study the connectivity and correlations between these RGCs, in order to determine if they use correlated activity to signal object position information to the brain. Next generation efforts to restore sight using retinal prosthetics will require a description of the behavior of all retinal ganglion cells in order to provide the sensory fidelity necessary for a normal lifestyle. My work goes beyond current generalized descriptions of RGCs to examine the fine-scale effects of spatial asymmetries in receptive field organization, which I believe is necessary for accurate signal replication. The results of this project will inform our understanding of networks of neurons, and their mechanisms for sensory feature extraction and population coding. This work is fundamental to our understanding of dysfunction in disease, both in the retina and in other sensory brain areas. Understanding of retinal systems will be important in the diagnosis and clinical research of degenerative retinal disease.